Aviation 101 : Flight Dynamics

To most people, the sky is the limit.

To those who love aviation, the sky is home.

All vehicles are free to operate in three dimensions i.e the longitudinal, vertical and horizontal axes.

In an aircraft, this movement are known by Pitch, Yaw and Roll.

Pitch

Motion about the lateral axis is called pitch and it’s a measure of how far an airplane’s nose is tilted up or down.

This is controlled by the elevator.

Yaw

Motion about the perpendicular axes is called yaw and for aircraft it determines which way the nose is pointed (Note: Aircraft do not necessarily fly in the same direction as the nose is pointed if there are significant winds.)

This is controlled by the movement of the rudder

Roll

Motion about the longitudinal axis is termed roll and in aircraft determines how much the wings are banked.

This is controlled by the movement of the aileron.


         The position of the Aileron, Elevator and the Rudder on an airplane


Where do you use it ?

There are a wide variety of times where all the three have to be employed. One such that crosses my mind is the Crosswind Landing

Crosswind landing is a landing maneuver in which a significant component of the prevailing wind is perpendicular to the runway center line.

The above maneuver is known as Crabbing

                                                   Source

Some more examples

One need not restrict the usage of these terms merely to aircrafts, but can extend it other objects of interest as well.

Cars also experience pitch, roll, and yaw, but the amounts are relatively small and are usually the result of the suspension reacting to turns, accelerations, and road conditions.

                                                  Source

For a human- Pitch is like saying Yes. Yaw is when you say No! And roll is when you just wave your head.

Pitch, Yaw and Roll and thats all there is to it.

Have a good one!!!

7

In 1984 NASA Dryden Flight Research Center and the Federal Aviation Administration (FAA) teamed-up in a unique flight experiment called the Controlled Impact Demonstration (CID), to test the impact of a Boeing 720 aircraft using standard fuel with an additive designed to supress fire. The additive FM-9, a high molecular-weight long chain polymer, when blended with Jet-A fuel had demonstrated the capability to inhibit ignition and flame propagation of the released fuel in simulated impact tests.

Antimisting kerosene (AMK) cannot be introduced directly into a gas turbine engine due to several possible problems such as clogging of filters. The AMK must be restored to almost Jet-A before being introduced into the engine for burning. This restoration is called “degradation” and was accomplished on the B-720 using a device called a “degrader”. Each of the four Pratt & Whitney JT3C-7 engines had a “degrader” built and installed by General Electric (G.E) to break down and return the AMK to near Jet-A quality.

In addition to the AMK research the NASA Langley Research Center was involved in a structural loads measurement experiment which included having instrumented dummies filling the seats in the passenger compartment. Before the final flight on December 1, 1984, more then four years of effort passed trying to set-up final impact conditions considered survivable by the FAA. During those years while 14 flights with crews were flown the following major efforts were underway: NASA Dryden developed the remote piloting techniques necessary for the B-720 to fly as a drone aircraft; General Electric installed and tested four degraders (one on each engine); and the FAA refined AMK (blending, testing, and fueling a full size aircraft). The 14 flights had 9 takeoffs, 13 landings and around 69 approaches, to about 150 feet above the prepared crash site, under remote control. These flight were used to introduce AMK one step at a time into some of the fuel tanks and engines while monitoring the performance of the engines. On the final flight (No. 15) with no crew, all fuel tanks were filled with a total of 76,000 pounds of AMK and all engines ran from start-up to impact (the flight time was 9 minutes) on the modified Jet-A.

The CID impact was spectacular with a large fireball enveloping and burning the B-720 aircraft. From the standpoint of AMK the test was a major set-back, but for NASA Langley, the data collected on crashworthiness was deemed successful and just as important.

Photos and text: NASA DFRC

9

Bell X-22 experimental tilting ducted fan V/STOL (vertical and/or short take-off and landing) aircraft.

Takeoff was to selectively occur either with the propellers tilted vertically upwards, or on a short runway with the nacelles tilted forward at approximately 45°.

The program started in 1966, and was eventually cancelled in 1988, with only two units produced, the second being made after the first crashed. 

General characteristics

Crew: two + six passengers
Length: 39 ft 7 in (12.07 m)
Wingspan: 39 ft 3 in (11.96 m)
Wingspan (front wing): 22.916 ft (6.98 m)
Height: 20 ft 8 in (6.31 m)
Empty weight: 10,478 lb (4,753 kg)
Max takeoff weight: 17,644 lb (8,003 kg)
Powerplant: 4 × General Electric-YT58-GE-8D turboshaft engines, 1,267 hp (945 kW) each
Propellers: three-bladed propellers mounted in wingtip swivelling ducts, 7 ft 0 in (2.13 m) diameter

Performance

Maximum speed: 221 kn (254 mph; 409 km/h)
Service ceiling: 27,800 ft (8,500 m)
Hover ceiling in ground effect : 12,000 ft (3,658 m)
Hover ceiling out of ground effect : 6,000 ft (1,829 m)